66 research outputs found
Cannabis in Asia: its center of origin and early cultivation, based on a synthesis of subfossil pollen and archaeobotanical studies
Biogeographers assign the center of origin of Cannabis to Central Asia, mostly based on wildtype plant distribution data. We sought greater precision by adding new data: 155 fossil pollen studies (FPSs) in Asia. Many FPSs assign pollen of Cannabis or Humulus (C-H) to collective names (e.g., Cannabis/Humulus or Cannabaceae). To dissect these aggregate data, we used ecological proxies. C-H pollen in a steppe assemblage (with Poaceae, Artemisia, Chenopodiaceae) was identified as wild-type Cannabis. C-H pollen in a forest assemblage (Alnus, Salix, Quercus, Betula, Robinia, Juglans) was identified as Humulus. C-H pollen curves that upsurged alongside crop pollen were identified as cultivated hemp. Subfossil seeds (achenes) at archaeological sites also served as evidence of cultivation. FPSs and archaeological sites were mapped using geographic information system (GIS) software. The oldest C-H pollen consistent with C. sativa dated to 19.6 million years ago (mya), in northwestern China. However, Cannabis and Humulus diverged 27.8 mya, based on molecular clock analysis. We bridged the temporal gap between the divergence date and the oldest pollen by mapping the earliest appearance of Artemisia. These data converge on the northeastern Tibetan Plateau, which we deduce as the C. sativa center of origin. This co-localizes with the first steppe community that evolved in Asia. From there, Cannabis first dispersed west (Europe by 6 mya) then east (eastern China by 1.2 mya). Cannabis pollen in South Asia appeared by 32.6 kya. The earliest Cannabis seeds were found in Japan, 10,000 BCE, followed by China
COSMOS2020: Identification of High-z Protocluster Candidates in COSMOS
We conduct a systematic search for protocluster candidates at in
the COSMOS field using the recently released COSMOS2020 source catalog. We
select galaxies using a number of selection criteria to obtain a sample of
galaxies that have a high probability of being inside a given redshift bin. We
then apply overdensity analysis to the bins using two density estimators, a
Weighted Adaptive Kernel Estimator and a Weighted Voronoi Tessellation
Estimator. We have found 15 significant () candidate galaxy
overdensities across the redshift range . The majority of the
galaxies appear to be on the galaxy main sequence at their respective epochs.
We use multiple stellar-mass-to-halo-mass conversion methods to obtain a range
of dark matter halo mass estimates for the overdensities in the range of
, at the respective redshifts of the
overdensities. The number and the masses of the halos associated with our
protocluster candidates are consistent with what is expected from the area of a
COSMOS-like survey in a standard CDM cosmology. Through comparison
with simulation, we expect that all the overdensities at will evolve
into a Virgo-/Coma-like clusters at present (i.e., with masses ). Compared to other overdensities identified at
via narrow-band selection techniques, the overdensities presented
appear to have higher stellar masses and star-formation rates.
We compare the evolution in the total star-formation rate and stellar mass
content of the protocluster candidates across the redshift range
and find agreement with the total average star-formation rate from simulations.Comment: 52 pages, 32 figues, 18 tables, main text is 30 pages, appendix is 22
pages, to be published in Ap
Obesity, the Endocannabinoid System, and Bias Arising from Pharmaceutical Sponsorship
Previous research has shown that academic physicians conflicted by funding from the pharmaceutical industry have corrupted evidence based medicine and helped enlarge the market for drugs. Physicians made pharmaceutical-friendly statements, engaged in disease mongering, and signed biased review articles ghost-authored by corporate employees. This paper tested the hypothesis that bias affects review articles regarding rimonabant, an anti-obesity drug that blocks the central cannabinoid receptor.A MEDLINE search was performed for rimonabant review articles, limited to articles authored by USA physicians who served as consultants for the company that manufactures rimonabant. Extracted articles were examined for industry-friendly bias, identified by three methods: analysis with a validated instrument for monitoring bias in continuing medical education (CME); analysis for bias defined as statements that ran contrary to external evidence; and a tally of misrepresentations about the endocannabinoid system. Eight review articles were identified, but only three disclosed authors' financial conflicts of interest, despite easily accessible information to the contrary. The Takhar CME bias instrument demonstrated statistically significant bias in all the review articles. Biased statements that were nearly identical reappeared in the articles, including disease mongering, exaggerating rimonabant's efficacy and safety, lack of criticisms regarding rimonabant clinical trials, and speculations about surrogate markers stated as facts. Distinctive and identical misrepresentations regarding the endocannabinoid system also reappeared in articles by different authors.The findings are characteristic of bias that arises from financial conflicts of interest, and suggestive of ghostwriting by a common author. Resolutions for this scenario are proposed
Size - Stellar Mass Relation and Morphology of Quiescent Galaxies at in Public Fields
We present the results of a systematic study of the rest-frame optical
morphology of quiescent galaxies at using the Near-Infrared Camera
(NIRCam) onboard . Based on a sample selected by color or
color, we focus on 26 quiescent galaxies with
at with publicly
available data. Their sizes are constrained by fitting the S\'ersic
profile to all available NIRCam images. We see a negative correlation between
the observed wavelength and the size in our sample and derive their size at the
rest-frame taking into account this trend. Our quiescent
galaxies show a significant correlation between the rest-frame size and the stellar mass at . The analytical fit for them at
implies that our size - stellar mass relations
are below those at lower redshifts, with the amplitude of
at . This value agrees with the
extrapolation from the size evolution of quiescent galaxies at in the
literature, implying that the size of quiescent galaxies increases
monotonically from . Our sample is mainly composed of galaxies with
bulge-like structures according to their median S\'ersic index and axis ratio
of and , respectively. On the other hand, there is a
trend of increasing fraction of galaxies with low S\'ersic index, suggesting
might be the epoch of onset of morphological transformation with a
fraction of very notable disky quenched galaxies.Comment: 23 pages, 16 figures, 2 tables; submitted to Ap
TRY plant trait database â enhanced coverage and open access
Plant traits - the morphological, anatomical, physiological, biochemical and phenological characteristics of plants - determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of traitâbased plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits - almost complete coverage for âplant growth formâ. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and traitâenvironmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives
A.T. Still Quote Collection
A page of quotations collected by Dr. McPartland from Doctor A.T. Still in the Living: His Concepts and Principles of Health and Disease by R.E. Truhlar and Dr. A.T. Still.https://dune.une.edu/mcpartlandcollection/1000/thumbnail.jp
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